lake, do you guys use mediacat, part smart, or something else at the shop and/or parts counter?
Moddin my 026 muffler
- Thread starter Bowtie
- Start date
Help Support Arborist Forum:
lake, do you guys use mediacat, part smart, or something else at the shop and/or parts counter?
Lakeside53
Stihl Wrenching
Mediacat - Partsmart has been discontinued for Stihl...
We've got an older verison of mediacat, but been using partsmart, and were originally told it was discontinued but we just upgraded our partsmart and got a new update for stihl with it also. So i dunno. I am somewhat anti mediacat, but that's primarily cause it saves us time to use one software suite for multiple lines. Right now we have stihl, husky, gravely, honda, toro, hustler, briggs, kohler, and kawasaki engines all on part smart. Lately it seems that a lot of vendors want us to use the IPL's on the manufacturer websites. I don't want to have to rely on my internet connection to look up parts.
Bowtie
Gearhead
LMAO, I just got done tearin that saw apart. Its a Walbro WT-403A with 833 above it when carb is upside down from mounted direction. So i may be ok, if it tachs out ok?
Lakeside53
Stihl Wrenching
Maybe.... Check it...
You always be happier with an adjustible carb... WT194 is the best; WT426can be "o.k." depending on the extent of your mods.
You always be happier with an adjustible carb... WT194 is the best; WT426can be "o.k." depending on the extent of your mods.
Bowtie
Gearhead
Sweet. I worship Lakeside and Ultra. I tried to rep both of yas, but wont let me, says I gotta spread the love a little more first.....png "Love :heart:")
Sweet. I worship Lakeside and Ultra. I tried to rep both of yas, but wont let me, says I gotta spread the love a little more first....
Are you a saw addict yet!!!!!!!!!!!!!!!!!
Thats all that matters.....
.
Bowtie
Gearhead
hahahahaa, my wife still pissed that I bought that 290. Yep, I got it. Soon as this 026 is fixed Im moddin the 034. Then we will find out if I will actually wait till the warranty expires to mod the 290. I gotta say this, the 290 is on its 4th tank of fuel, I used it all day, and Im impressed with its power, even though its a heavy saw.
Bowtie
Gearhead
Hey Lake, I tached my 026 tonight. If the tach is even close its taching at 15,200. yeah, thats nuts. I got a WT 426 carb off Ebay, new, for 23 bucks. You think this carb can make my 026 all happy? If not I'll find a wt194. Did a search for them, none available off Ebay anyways.
Lakeside53
Stihl Wrenching
Just try it. Sometimes you run out of adjustment with an aggressive muffler mod. If so you can change jets. The WT194 is available NEW from any Walbro dealer.
Bowtie
Gearhead
Got this saw running, and went to tune it. When I run at WOT, it revs to around 12,000, then slowly keeps climbing rpm to over 15,000 no matter where I tune the h screw. Could this be a leak somewhere? I also have a new fuel leak, but I dont believe that is related, but i need to diagnose this problem this weekend when I replace fuel line, filter, and impulse hose.
Lakeside53
Stihl Wrenching
That could be a a stiff metering diaphragm, the WT426 running out of adjustment (you can only adjust about 15% of the H fuel flow), or an air leak in a seal or your fuel line (air gets into the line...), etc...
Last edited:
Bowtie
Gearhead
Seems to be running lean at max throttle by my ear.( my new Ebay tach already took a dump on me ) Im gonna replace fuel and impulse line and filter as I have them ordered. See what happens there, then proceed with possibly a 194 walbro like Lakeside said I should have in the first place... Sometimes my stubborness isnt my friend.
Sometimes my stubborness isnt my friend.
Bowtie
Gearhead
I may also swap from new metering diaphram to old diaphram and check that if ya think its wort trying.
Lakeside53
Stihl Wrenching
Nope.. if it's new leave it.
Erick
Addicted to ArboristSite
Sounds like your carb may be working fine and thats why your saw stops at 12,000, the creeping up to 15,000 sounds like an air leak to me.
That fuel leak may be allowing air into the system causing the lean condition????
Other possibilities??
Check your carb seal at the manifold for leaks, sometimes a small piece of debris gets in there or the retainers for the manifold it's self get bent, twisted, or knocked out of alignment causing it not to seal properly.
Check the impulse line as well, they get brittle with age and if you've moved it much it may have a tiny crack allowing air into the system.
I have the 426 on my muff modded 260 and it works fine wouldn't imagine you would need to go to the 194 for just a muffler modifucation.
Did you ever try the saw with the original 403 carb?? If not might try bolting it back on and see what you get it may identify or eliminate your new carb as the problem.
My guess from way over here is that fuel leak, get it fixed and see what she does then.
Lakeside53
Stihl Wrenching
I've seen several 426 either run out of H adjustment or get very close to that point with standard jets. Most do work fine though.
Bowtie
Gearhead
The fuel leak was the tank vent valve. Got another ordered. After shuttin the saw off, tank built pressure, floodin the carb out. I think I got the saw close to right. Did air test today, no leak detected. Im going to run it a little bit, then check again. it is 4-stroking at WOT, and plug color looks good. I need to buy another tach...Ebay tach 1 week old and died...
If I end up rejetting, can anyone tell me what size jet is stock on the 426, and what size I would have the most luck ordering?
If I end up rejetting, can anyone tell me what size jet is stock on the 426, and what size I would have the most luck ordering?
Lakeside53
Stihl Wrenching
The standard jet if 0.48mm; the high altitude jet is 0.46... Look at it with a magnifying glass and you'll see the size on top...
The tank vent is not what stops the "leak" - it's designed to "leak". Inside the tank under the vent is a rubber flapper valve (depends on the model) -that's what stops only the outbound leak! and.. it's supposed to hold all pressure in the tank.. Early models has no flapper valve and will "leak" both ways a little..
Sorry... but if your tank pressure caused your inlet needle to pop-off, you have something wrong in the carb. You can pump up that carb to 15-20psi before it will pop-off, and your fuel pressure won't even get remotely close to that.
The tank vent is not what stops the "leak" - it's designed to "leak". Inside the tank under the vent is a rubber flapper valve (depends on the model) -that's what stops only the outbound leak! and.. it's supposed to hold all pressure in the tank.. Early models has no flapper valve and will "leak" both ways a little..
Sorry... but if your tank pressure caused your inlet needle to pop-off, you have something wrong in the carb. You can pump up that carb to 15-20psi before it will pop-off, and your fuel pressure won't even get remotely close to that.
Bowtie
Gearhead
Ok, Lake, here is what happened. I ran the saw, shut it off. let it sit. Gas was coming out from the carb. I took the little orange valve out in the tank vent. Then it quit producing pressure at the fuel line to the carb. Is it supposed to have that pressure at the fuel line entrance to the carb after shut down? Im not saying there isnt anything wrong with the carb, I bought it off ebay, and never tore it apart. it was supposed to be new, but you know how that goes sometimes. I will wait for the new valve, install it, and go from there. By the way Lakeside, you have any walbro 194 carbs you would part with? I should have took your advice and bought that one from the beginning.
